<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title>9-变量的命名规则</title>
	</head>
	<body>
		<script type="text/javascript">
			//1.严格区分大小写
			var username = 'zhangwuji';
			var userName = 'zhangguorong';
			//alert(username+userName);
			//2.不能以数字开头
			//var 18age;
			//console.log('>>>>>>>>>>>>>>>>>>>>')
			//3.变量名不能是关键字和保留字
			//var while;
			
			//var nandeornvde;
			
		</script>

	</body>
</html>
